Houthi rebels have been fighting with coalition forces, led by Saudi Arabia, since the Yemeni Civil War began in 2015. Last month, after a missile was launched at Saudi Arabia, a blockade was established in Yemeni ports.

According to the UK official, Trump told May that Saudi Crown Prince Mohammed bin Salman needs to do more to help prevent the humanitarian crisis that has left innocent civilians suffering.

Trump spoke with King Salman bin Abdulaziz Al Saud of Saudi Arabia on Wednesday. According to a White House readout of the call, the king "briefed the president on Saudi Arabia's plan to alleviate the humanitarian crisis in Yemen. The leaders discussed the importance of engaging the United Nations to hold Iran accountable for its repeated violations of international law and agreed on the importance of reinvigorating a political process to end the war in Yemen."